JPH0922644A - Temperature fuse device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a temperature fuse device to open a power supply circuit, although being easy to install and having simple constitution, if a condition that may lead to heating or firing occurs and depending on the heating temperature of a wire. SOLUTION: A path to which battery output that serves as the power supply for a circuit or equipment is directly applied is cut off, and the conductor of a lead wire 11 is connected to that of a lead wire 15 with low-melting-point solder 16. Then the lead wire 11 is guided by projections 12a, 12b and placed in a horizontal position, while the lead wire 15 is passed through the inside of a fixing hook 14 and then laid to ride over a projection 13 provided on the same plane where the projections 12a, 12b are formed. If excess current flows through the connection, the low-melting-point solder 16 is melted by the heat of the connection, and the end of the lead wire 15 is deformed in such a manner as to be extended because of its elastic force, whereby the conductors are separated from each other to cut off the path.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a temperature fuse device for an apparatus using a battery as a power source, which detects an abnormality due to discharge of an excessive current and shuts off a power supply system.

[0002]

2. Description of the Related Art For example, a camera is constructed so that a manganese battery, an alkaline battery, a nickel-cadmium battery or the like can be exchangeably mounted on a grip portion, a power unit or the like. Usually, a plurality of such batteries are used, and the batteries are loaded in the battery accommodating portion according to the determined polarity direction. After loading, the cap is mounted and fixed by screwing or the like.

However, when the user is using the needle, coin,
When a battery is loaded with a conductor such as a metal piece accidentally dropped in the battery compartment, or when the battery is loaded with the polarity reversed, the power supply system becomes short-circuited or short-circuited, Excessive current may cause an accident such as ignition or smoking, which may damage the product as well as the human body. Further, if a conductive foreign substance is mixed in during the manufacturing process, or if there is a design failure or the like, control malfunction and circuit destruction may be caused, and the product may be damaged. Therefore, conventionally, measures have been taken to coat the mounted circuit with a moisture-proofing agent or the like to improve the insulating property or prevent the reverse loading of the battery.

[0004]

However, as described above, the countermeasures for coating application and preventing reverse insertion of the battery cannot be said to be perfect against a large number of various internal and external factors. For example, when the output part is exposed to the exterior part and the like, if a careless short circuit occurs, abnormal heat generation, ignition, etc. occur.

As a means for solving this, it is possible to use a fuse. There are various types of fuses, such as tubular type, lead wire type, chip type, etc., in terms of shape, and in terms of characteristics, the current capacity, fusing time, set temperature, etc. are abundant. . However, in mounting these, a fuse of cylindrical type requires a fuse clip and a fuse holder. In addition, the lead wire type requires special consideration in mounting work (such as not applying force to the lead wire, and applying force evenly to the fuse body and the lead wire).

Therefore, an object of the present invention is to provide a thermal fuse device which is easy to mount and has a simple structure, and which can be cut off when a condition leading to heat generation or ignition occurs.

[0007]

In order to achieve the above object, the present invention provides a lead wire by cutting the path in which the output of a battery serving as a power source of a circuit or a device is directly applied. And each core wire of the lead wire are connected by low melting point solder. At this time, the lead wire is placed horizontally while being guided by the protrusion, and after passing through the fixed hook,
Wiring is performed so as to get over the protrusion provided on the same plane where the protrusion is formed. When an excessive current flows through the connecting portion, the heat generated causes the low-melting-point solder to melt and the tip portion of the lead wire changes so as to expand due to the elastic force, the core wires are separated from each other, and the path is cut off.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The structure for realizing the object of the invention according to the present application is, as described in claim 1, in the middle of a route where the output of a battery serving as a power source of a circuit or a device is directly applied. And a low-melting-point solder that connects the parts and an urging means that applies an elastic force that separates one of the wire rods of the connection part from the other when the fuse is melted by heat generated by energizing the path. I am trying.

According to this structure, when a short circuit occurs in the battery, a large current flows in the short circuit path to heat the wire itself and melt the low melting point solder. Since one of the connecting portions is urged by the urging means, the core wires and the like of the connecting portions are separated from each other as the solder is melted, and the current path is cut off. Therefore, a device having the same function as the fuse can be configured with a simple configuration without using the fuse and its holding component, and the accident can be prevented from spreading.

As a concrete constitution for realizing the object of the invention according to the present application, as described in claim 2, the path of the cutting portion is made of a metal power source contact, one of which is in contact with one of the electrodes of the battery. One can be the lead and the other the lead.

According to this structure, by using one of the connection parts as a metal power source contact piece, for example, the electrode of the battery storage part can be diverted, and the structure can be simplified and the number of parts can be reduced. become.

Another specific configuration for achieving the object of the invention according to the present application is, as described in claim 3, in that the paths of the cut portions are both lead wires, and the connecting portions are made of copper. The net can be laid.

According to this structure, the lead wire and the low melting point solder can be used alone, and the number of parts can be minimized and the structure can be simplified. The copper net absorbs the molten solder after the solder in the connecting portion is melted, and prevents the solder from re-adhering to the connecting portion.

Another specific configuration for achieving the object of the invention according to the present application is, as described in claim 4, in which the urging means is configured to connect at least one of the paths of the cutting portion from a position before connection. The structure may be such that an elastic force or an urging force to move is applied.

According to this structure, the elasticity of the lead wire itself is used as the urging means for separating the core wires or the like of the connection portion from each other when the solder is melted, or the tip portion of the lead wire is forcedly applied. Bending or fluctuation can be caused in the path, and the path can be blocked. As a result, the shutoff operation can be performed with an extremely simple configuration.

Further, the structure for realizing the object of the invention according to the present application is, as described in claim 5, within a substrate or between substrates in which a pattern through which the output of a battery serving as a power source directly flows is formed. An electric element or a metal piece having a conductive portion that is disposed over the electric element or metal piece and that connects the patterns, and a low melting point solder that connects the conductive portion of the electric element or the metal piece to each pattern of the substrate. And a biasing member that biases the electric element or the metal piece in a direction away from the printed circuit board.

According to this structure, the pattern formed on the substrate is used as a flow path, and the interruption between the patterns is performed by the interposition of the electric parts. Normally, the conductor of the electric part connects the patterns. When an abnormal current flows, the path is cut off by utilizing the melting of the low melting point solder used for connection with the pattern. As a result, a device having the same function as the fuse can be configured with a simple configuration without using the fuse and its holding component, and it is possible to prevent the accident from spreading.

Further, the structure for realizing the object of the invention according to the present application is, as described in claim 6, arranged in the middle of the path to which the output of the battery serving as the power source of the circuit or device is directly applied. A pair of contact pieces made of a conductive material that are provided and positioned so that the tip portions of the contact pieces overlap each other, and a low melting point that interposes on one side of the pair of contact pieces while keeping the tip portions of the pair of contact pieces in contact with each other. It is equipped with a lump of solder.

According to this structure, the pair of contact pieces are arranged in the middle of the flow path, and the electrically connected state is maintained while being pressed by the solder mass. When an excessive current flows through the contact piece, the contact piece heats up and melts the solder mass in contact with it. With this melting, the connecting portions of the contact pieces are separated from each other, and the flow is cut off. As a result, a device having the same function as the fuse can be configured with a simple configuration without using the fuse and its holding component, and it is possible to prevent the accident from spreading.

Another specific configuration for achieving the object of the invention according to the present application is, as described in claim 7, a third embodiment for a contact piece whose tip portion changes in accordance with melting of the solder mass. Of the contact pieces are arranged parallel to each other so as to come into contact with the changing contact pieces in accordance with the melting of the solder mass.

According to this structure, when the solder mass is melted by the heat generated by the excessive current, the contact piece located in the middle fluctuates according to the deformation of the solder mass and contacts the third contact piece in the process. . Therefore, a device having both a fuse function and a switch function can be obtained, and the warning circuit can be operated at the same time when the power supply circuit is cut off.

[0022]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view showing a thermal fuse device according to the present invention, and FIG. 2 is a perspective view showing an external power supply device of a camera to which the present invention is applied.

Explaining the configuration of FIG. 2, the external power supply device includes a battery magazine 1 in which four batteries 1b are loaded in a battery holder 1a, a magazine storage section 3 and a grip section 4 in which the battery magazine 1 is stored. And a battery pack 2 including The grip portion 4 is provided upright on one end of the battery pack 2.
The horizontal portion of the battery pack 2 forms a holder 5, which can be attached to and detached from the bottom surface of the camera body (not shown).

The camera body and the battery pack 2 can be fixed to each other by screwing the screw 6 projecting on the upper surface of the battery pack 2 and a tripod screw hole provided on the bottom surface of the camera body. In order to rotate the screw 6, a knob 7 that fixes the lower end of the screw 6 is rotatably arranged in the battery pack 2. Further, the grip portion 4 has a shape that covers a part of the camera body.

Further, a terminal plate 8 connected to an electrode at the tip of the battery magazine 1 is provided at the rear end of the magazine storage portion 3 of the battery pack 2. A connection contact piece 9 that comes into contact with the connection terminal on the camera body side is provided near the base of the grip portion 4 on the battery pack 2. When the power of the battery 1b is supplied to the camera body side via the connecting piece 9, the camera is connected to the vertical position release button 1c provided in the battery magazine 1.

(First Embodiment) Next, the configuration of the first embodiment shown in FIG. 1 will be described.

Protrusions 12a and 12b for guiding the lead wire 11 are erected on one surface of the main body 10. Further, the rectangular protrusion 1 is opposed to the tip of the lead wire 11.
3 (the upper surface is provided with curved surfaces on both sides in the insertion direction of the lead wire). Further, a substantially U-shaped fixed hook 14 is integrally provided with the main body 10 on the side wall of the main body 10 adjacent to the protrusion 13. A lead wire 15 is inserted from the lower side into a space formed between the fixed hook 14 and the main body 10, and a tip portion of the lead wire 15 rides over the protrusion 13 and is guided to a position overlapping the tip portion of the lead wire 11. There is. Therefore, the lead wire 15 is bent in the shape of a dogleg in the vicinity of the main body 10. Further, the core wire portion at the tip of the lead wire 11 and the core wire portion at the tip of the lead wire 15 are
Brazing is performed using the low melting point solder 16.

The low melting point solder 16 is an alloy containing at least two kinds of tin, lead, indium, zinc, antimony, cadmium and the like, and its melting point is 183 ° C. or lower.

In the above structure, the connecting piece 9 of the battery pack 2 (on which the battery magazine 1 in which the battery 1b is loaded) shown in FIG. 2 is inadvertently short-circuited by an external factor, or If the power supply circuit is left short-circuited due to internal factors such as foreign metal particles in the external power supply, an excessive current flows. Due to this excessive current, the battery, the circuit to which the excessive current flows, and the members in contact with them generate heat. When the portion connected by the low melting point solder 16 generates heat due to an excessive current and reaches a certain temperature, the low melting point solder 16 connecting the lead wire 11 and the lead wire 15 is melted.

On the other hand, the tip end portion of the lead wire 15 is laid so that the elastic force can be retained so that the linear shape is restored to the linear state. Therefore, when the low melting point solder 16 is melted and the connection between the lead wire 11 and the lead wire 15 is broken, the protrusion 1
3 serves as a fulcrum, the fixed hook 14 serves as a lever, and the molten portion moves upward as shown by a dotted line to reach a stable state. As a result,
The electrical connection between the lead wire 11 and the lead wire 15 is cut off, the subsequent power supply to the short-circuited part is cut off, and heat generation is stopped. That is, the same state as when the fuse is blown is obtained.

As described above, it is possible to obtain an inexpensive and easy-to-handle thermal fuse device without increasing the number of parts in the case of a short-circuited state which may cause smoking or ignition if left unattended.

(Second Embodiment) FIG. 3 is a perspective view showing a second embodiment of the thermal fuse device according to the present invention. The same reference numerals are used for the same elements as those in the above-described embodiment, and thus the duplicated description will be omitted.

An L-shaped metal power source contact piece 18 is fixed to two orthogonal surfaces of the main body 17 via a holder 19 formed by molding or the like. An electrode portion 18a is bulged in a circular shape at one end of the power source contact piece 18, and corresponds to one electrode plate of the terminal plate 8 shown in FIG. Furthermore,
At the other end (connection portion) of the power supply contact piece 18, a connection piece 18b processed into a linear shape is formed. The holder 19 is fixed to the main body 17 by screws 20.

Further, a columnar protrusion 21 is provided upright on the portion facing the mounting position of the holder 19, and the tip of the lead wire 11 is wound one turn. The core wire portion 11a exposed at the tip of the lead wire 11 and the power supply contact piece 18
The connection piece 18b is connected with the low melting point solder 16. When performing this soldering, the low melting point solder 16 is used for connection while pushing up the tip of the connecting piece 18b.

In the embodiment of FIG. 3, the connecting piece 9 of the battery pack 2 in which the battery 1b shown in FIG.
However, if the power supply circuit is inadvertently short-circuited due to an external factor or the power supply circuit is short-circuited due to an internal factor such as a metallic foreign substance in the external power supply, if it is left as it is, an excessive current flows in the battery. Due to this excessive current, the connection piece 18b and the wire portion 11a, to which the excessive current flows, generate heat. When the heat generating portion reaches the temperature level at which the low melting point solder 16 melts, the low melting point solder 16 connecting the power source contact piece 18 and the lead wire 11 melts.

On the other hand, the connecting piece 18b of the power source contact piece 18 is forcibly positioned above the steady state and the lead wire 11
Since the low melting point solder 16 melts, the tip of the connecting piece 18b is no longer restrained and returns from the solid line position to the dotted line position. As a result, the electrical connection between the lead wire 11 and the power supply contact piece 18 is cut off, the power supply to the short-circuit portion is cut off thereafter, and heat generation is stopped. That is,
The fuse is blown and the same condition occurs.

(Third Embodiment) FIG. 4 is a perspective view showing a third embodiment of the temperature fuse device according to the present invention. In addition, in FIG. 4, a part of the main body and the like is shown in a sectional view. Further, the same reference numerals are used for the same components as those used in the above-mentioned embodiment.

In the present embodiment, the main body 17 is made of an insulating material such as synthetic resin, and the power supply contact piece 18 has a screw 2 on the mounting surface.
Attached by 0. On the side opposite to the mounting position of the power source contact piece 18, a fixed hook 22 having the same structure as that used in the embodiment of FIG. On the mounting surface near the fixed hook 22, a recess 17 having a collar 17a is formed.
b is provided, and a push-up spring 23 having a cross section of “Ω” is fitted in the recess 17b.

The lead wire 15 is inserted into the fixed hook 22 from below, and is further laid across the upper surface of the push-up spring 23 to a position where the connecting wire 18b of the power source contact piece 18 and the core wire 15a of the lead wire 15 overlap. It After that, the low melting point solder 16 is used for soldering while pushing down the tip end of the lead wire 15 so as not to lose the elastic force.

According to the embodiment of FIG. 4, the connecting piece 9 of the battery pack 2 shown in FIG.
If the power supply circuit is inadvertently short-circuited due to an external factor or the power supply circuit is short-circuited due to an internal factor such as a metal foreign substance in the external power supply, an excessive current flows in the battery if left as it is. Due to this excessive current, the connection piece 1
8b and the core of the lead wire 15 also generate heat. When the heat generating portion reaches the temperature level at which the low melting point solder 16 melts, the low melting point solder 1 connecting the power supply contact piece 18 and the lead wire 11 to each other.
6 melts.

On the other hand, the connection piece 18b of the power supply contact piece 18 is forcibly positioned above the steady state and is lead wire 11.
Since the low melting point solder 16 melts, the tip of the connecting piece 18b is no longer restrained and returns from the solid line position to the dotted line position. As a result, the electrical connection between the lead wire 11 and the power supply contact piece 18 is cut off, the power supply to the short-circuit portion is cut off thereafter, and heat generation is stopped. As described above, according to this embodiment, a device having the same function as the fuse can be formed without using the fuse.

(Fourth Embodiment) FIG. 5 is a perspective view showing a fourth embodiment of the thermal fuse device according to the present invention. The same reference numerals are used for the same components as those used in the above-mentioned respective embodiments. On both sides of the mounting surface of the rectangular main body 24, columnar protrusions 25a and 25b and protrusions 26a and 26b are provided upright in parallel with each other. Protrusion 25a,
25b and the protrusions 26a and 26b are provided so as to be aligned with each other. Further, in the central portion of the mounting surface of the main body 24,
A copper wire net 27 for absorbing the solder is installed. Further, a trapezoidal protrusion 28 having the same structure as the protrusion 13 in FIG. 1 is provided between the protrusions 25a and 25b and the copper wire net 27.

With such a structure, the protrusions 25a, 2
A lead wire 29 is fitted between the 5b, and the tip end of the lead wire 29 rides on the protrusion 28 and is laid so that the core wire 29a is located at the center of the copper wire net 27. Also, the protrusions 26a and 26b
A lead wire 30 is fitted in between, and the core wire 30a is laid so as to overlap the core wire 29a. Next, the core wire 29 a and the core wire 30 a are soldered with the low melting point solder 16.

According to the embodiment shown in FIG. 5, as in each of the above-mentioned embodiments, if a short circuit occurs due to some cause, an excessive current flows in the power supply if it is left as it is. The excessive current also heats the core wire 29a of the lead wire 29 and the core wire 30a of the lead wire 30.
When the melting temperature level of 6 is reached, the low melting point solder 16 connecting the lead wires 29 and 30 is melted.
The melted solder is sucked up by the copper wire net 27 so that the residual solder on each core wire of the lead wire 29 and the lead wire 30 is reduced.

On the other hand, the tip of the lead wire 29 is forcibly positioned below the steady state and soldered to the lead wire 30. Therefore, when the low melting point solder 16 melts, the tip of the lead wire 29. Is no longer bound. As a result, the electrical connection between the lead wire 29 and the lead wire 30 is cut off, the power supply to the short-circuited portion is cut off thereafter, and heat generation is stopped.
As described above, according to this embodiment, a device having the same function as the fuse can be formed without using the fuse.

(Fifth Embodiment) FIG. 6 is a sectional view showing a fifth embodiment of the temperature fuse device according to the present invention. The same reference numerals are used for the same components as those used in the above-mentioned respective embodiments.

The present embodiment is characterized in that the temperature fuse device is provided in the circuit board. Mounting flexible board 31 and mounting flexible board 3 arranged on the same plane
A mounting electric element 33 (a capacitor, a resistor or the like, or a metal piece of a conductor or the like) is arranged between the two adjacent to each other, and both sides (board side) of the mounting electric element 33 are provided with a low melting point solder 34a, 34b to form a pattern of a power circuit on the board. Connected to. The mounting electric element 33 is
The mounting flexible boards 31 and 32 partially or entirely have a portion for electrically connecting between the patterns. The mounting electric element 33 and the mounting flexible boards 31 and 32 include a main body (or a lid, a case, etc.) 35a made of resin or the like,
It is protected so as to be sandwiched by 35b. Further, in order to reduce the thickness of the entire device, a concave portion 35c is formed in a portion of the main body 35a facing the mounting electric element 33 and the low melting point solders 34a and 34b, and similarly, the concave portion 35c faces the mounting electric element 33 of the main body 35b. A recess 35d is formed in the portion. In addition, a biasing member 36 (coil spring) for pushing up the mounting electric element 33 toward the main body 35a side is disposed in the recess 35d.

In the above structure, if a short circuit occurs due to some cause in the state of (a), an excessive current will flow to the battery if it is left as it is. Due to this excessive current, the conductive portion of the mounting electric element 33 and the low melting point solder 34
a, 34b are also heated, and this heating part is low melting point solder 34a,
When the temperature level at which 34b is melted is reached, the low melting point solders 34a and 34b connecting the pattern and the conductive portion of the mounting electric element 33 are melted.

The fixing of the mounting electric element 33 is released due to this melting, but the mounting electric element 33 is pressed from the lower side to the urging member 3.
Since it is pushed up by 6, the mounting electric element 33 moves into the recess 35c of the main body 35a as shown in (b). As a result, the electrical connection between the pattern 31 and the pattern of the lead wire 32 is cut off, the power supply to the short-circuit portion thereafter is cut off, and heat generation is stopped. Thus, according to this embodiment, it is possible to form a device having the same function as the fuse without using the fuse.

In the embodiment shown in FIG. 6, the mounting flexible boards 31 and 32 are taken as an example, but the present invention is not limited to the flexible boards, and ordinary printed boards may be used. Further, although the mounting electric element 33 is provided between the two substrates, it may be provided within one substrate.

(Sixth Embodiment) FIG. 7 is a sectional view showing a sixth embodiment of the thermal fuse device according to the present invention. The same reference numerals are used for the same components as those used in the above-mentioned respective embodiments.

A gap is provided between the main body 37a and the main body 37b, and a part of the main body 37a near the main body 37b is cut away. An elastic metal contact piece 38 is fixed to the surface of the main body 37a. The tip of the contact piece 38 is bent into a semicircular shape, and this portion is located in the scraped portion. A recess 39 is formed on the surface of the scraped portion, and a block-shaped low melting point solder 40 (the diameter of which is smaller than the inner diameter of the recess 39) is disposed in the recess 39.

Further, one end of a plate-shaped metal contact piece 41 is fixed to the surface of the main body 37b. The tip of the contact piece 41 is arranged so as to be located between the tip of the contact piece 38 and the low melting point solder 40, and the three members in this portion are in electrical contact with each other. 38 and connecting piece 4
1 is conducting and is in a switch-on state. However, the tip end portion of the contact piece 41 is interposed between the contact piece 38 and the low melting point solder 40 in a state in which the elastic force that biases the low melting point solder 40 side is maintained.

In the above structure, if a short circuit occurs for some reason in the state of (a), an excessive current will flow in the battery if it is left as it is. Due to this excessive current, the contact piece 38 and the contact piece 41 also generate heat, and when the heat generating portion reaches a temperature level at which the low melting point solder 40 melts, the elliptical low melting point solder 40 melts and becomes short. . Following this change in shape, the tip of the contact piece 41 contacts the contact piece 38.
The contact piece 38 and the contact piece 4 in the process of moving away from
1 is disconnected as shown in (b). That is, it is in the same state as when the fuse is blown.

As a result, the power supply to the short circuit portion is cut off thereafter, and the heat generation is stopped. As described above, according to this embodiment, a device having the same function as the fuse can be formed without using the fuse.

In the embodiment shown in FIG. 7, the contact piece 38 is used.
Although the contact piece 41 and the contact piece 41 are arranged so as to extend from the opposite direction on the same line, they may be attached to a common main body in a state of being overlapped from the same direction.

(Modification) FIG. 8 is a sectional view showing a modification of the embodiment shown in FIG. While the configuration of FIG. 7 is a switch configuration of one circuit and one contact by turning on / off the contact piece 38 and the contact piece 41, this embodiment is an example of a switch type switch configuration of one circuit and two contact points. . For this purpose, a contact piece 42 is provided on the back surface of the main body 37a. The contact piece 42 is processed into a shape such that the back surface of the contact piece 41 can contact the contact piece 42 in the state of FIG. 7B. That is, it is composed of a flat plate portion for fixing to the main body 37a and a J-shaped portion formed at the tip thereof.

In this structure, the contact piece 38 and the contact piece 41 are in contact with each other in the state of FIG. 7A, but when the low melting point solder 40 is melted due to heat generation, (B)
Then, the tip end of the contact piece 41 changes in the direction of the arrow in FIG.
The connection of 1 is cut off, and at the same time, the contact piece 41 and the contact piece 42 contact each other, and the circuit is switched. By using this switching means, it is possible to issue an abnormality warning or the like.

FIG. 9 is a circuit diagram showing a warning display circuit constructed by using the switching means of FIG.

This warning display circuit can be provided in the battery pack 2 shown in FIG. 2, for example. Battery 1c
Has one end connected to one of the connecting pieces 9 and the other end having a connecting piece 41.
It is connected to the. In addition, the contact piece 38 has one of the connection pieces 9
Connected to one. Furthermore, the other end of the battery 1c and the contact piece 42
A circuit in which a resistor 43 and a light emitting diode 44 are connected in series is connected between the two.

In the normal state, the contact piece 42 and the contact piece 38 are formed.
Are in contact (indicated by the dotted line in FIG. 9), and the output of the battery 1c is applied to the connecting piece 9. However, when abnormal heat is generated, the low melting point solder 40 shown in FIG.
The contact of No. 1 is switched from the contact piece 38 to the contact piece 42. As a result, the light emitting diode 44 is energized through the resistor 43 and the light emitting diode 44 is turned on. This allows the user to know that an abnormality has occurred.

Although the light emitting diode 44 is driven in FIG. 9, an acoustic warning such as a buzzer may be given instead of or at the same time.

In the above description, an example in which the object of the present invention is applied to an external power supply device of a camera has been shown, but the present invention is not limited to such an application, and electronic equipment other than the camera, and Can be applied to stationary equipment other than the external power supply.

Further, in each of the above embodiments, the saddle-shaped projection is provided only on one of the lead wires of the connecting portion to give the elastic force, but the biasing means or the biasing means for moving in different directions may be used. You may make it provide an elastic force. By doing so, the reliability of interruption can be further improved.

[Correspondence between Invention and Embodiment] In the above embodiments, the low melting point solders 16, 34a, 34b correspond to the low melting point solders, and the functions of the protrusions 13, 23, 28 correspond to the urging means. The copper wire net 27 corresponds to a copper wire net, and the biasing member 36 corresponds to a biasing member. Furthermore, contact piece 3
8 and the contact piece 41 correspond to a pair of contact pieces made of the first and second conductive materials, and the low melting point solder 40 corresponds to a solder block.

[0067]

According to the invention as set forth in claim 1, a path having a low melting point for connecting this portion is cut in the middle of a path to which the output of a battery serving as a power source of a circuit or a device is directly applied. Since the solder and the biasing means for applying an elastic force that separates one of the wire rods of the connecting portion from the other at the time of fusing due to heat generated by energizing the path,
A device having the same function as the fuse can be inexpensively configured with a simple configuration without using the fuse and its holding component. This makes it possible to prevent the accident from spreading.

According to the second aspect of the present invention, the path of the cut portion is such that one of the paths is a metal power source contact piece that contacts one of the battery electrodes, and the other is a lead wire. It is possible to use the electrodes of
It is possible to reduce the number of parts.

According to the third aspect of the present invention, the routes of the cutting portions are both lead wires, and the connecting nets are laid with copper nets. Therefore, the number of parts is the smallest, and It can be the simplest configuration. Further, the copper net can absorb the molten solder after the solder at the connection portion is melted, and prevent the solder from re-adhering to the connection portion.

According to the invention described in claim 4, the urging means has a structure for imparting an elastic force or an urging force for moving at least one of the paths of the cutting portion from the position before the connection. Therefore, it becomes possible to perform the breaking operation with an extremely simple configuration.

According to the fifth aspect of the invention, the output of the battery serving as a power source is arranged inside or between the substrates on which the pattern is formed and the patterns are connected to each other. From the printed circuit board, an electric element or a metal piece having a conductive portion extending over it, a low melting point solder that connects the conductive portion of the electric element or the metal piece to each pattern of the board, and the electric element or the metal piece. Since a biasing member that biases away is provided, a device with the same function as the fuse can be configured with a simple configuration without using the fuse and its holding parts, and it is possible to prevent the spread of accidents. become.

According to the invention described in claim 6, it is arranged in the middle of the route to which the output of the battery serving as the power source of the circuit or the device is directly applied, and is positioned so that the tip portions overlap. Since a pair of contact pieces made of a conductive material and a low-melting-point solder mass to be interposed on one side of the pair of contact pieces while the tip portions of the pair of contact pieces are in contact with each other are provided, the same as a fuse A functional device can be obtained with a simple structure that is inexpensive, easy to handle and does not use a fuse and its holding parts. As a result, it is possible to prevent the accident from spreading.

According to the invention described in claim 7, the third contact piece is parallel to the contact piece whose tip portion changes in accordance with the melting of the solder mass and the fluctuation occurs in accordance with the melting of the solder mass. Since it is arranged so as to come into contact with the contact piece, a device having both a fuse function and a switch function can be obtained, and the warning circuit can be operated at the same time when the power supply circuit is cut off.

[Brief description of drawings]

FIG. 1 is a perspective view showing a thermal fuse device according to the present invention.

FIG. 2 is a perspective view showing an external power supply device of a camera to which the present invention is applied.

FIG. 3 is a perspective view showing a second embodiment of the thermal fuse device according to the present invention.

FIG. 4 is a perspective view showing a third embodiment of the thermal fuse device according to the present invention.

FIG. 5 is a perspective view showing a fourth embodiment of the thermal fuse device according to the present invention.

FIG. 6 is a sectional view showing a fifth embodiment of the thermal fuse device according to the present invention.

FIG. 7 is a sectional view showing a sixth embodiment of the thermal fuse device according to the present invention.

FIG. 8 is a sectional view showing a modification of the embodiment of FIG.

9 is a circuit diagram showing a warning display circuit configured by using the switching means of FIG.

[Explanation of symbols]

1b Battery 10, 17, 24, 35a, 35b, 37a, 37b
Main body 11, 15, 29, 30 Lead wire 11a, 29a, 30a Core wire 12a, 12b, 13, 21, 25a, 25b, 26
a, 26b, 28 Protrusion 14, 22 Fixing hook 16, 34a, 34b, 40 Low melting point solder 18 Power contact piece 18b Connection piece 23 Push-up spring 27 Copper wire net 31, 32 Mounted flexible board 33 Mounted electric element 36 Energizing member 38 , 41, 42 contact piece

Claims (7)

[Claims] 1. A disconnection state is set in the middle of a path to which an output of a battery serving as a power source of a circuit or a device is directly applied,
A low-melting-point solder for connecting this portion, and an urging means for applying an elastic force for separating one of the wire rods of the connecting portion from the other when the fuse is melted by heat generated by energizing the path. Temperature fuse device. 2. The thermal fuse device according to claim 1, wherein one of the paths of the cut portion is a metal power source contact piece that contacts one side of a battery electrode, and the other is a lead wire. . 3. The temperature fuse device according to claim 1, wherein the paths of the cut portions are both lead wires, and a copper net is laid at the connection portion. 4. The thermal fuse according to claim 1, wherein the urging means has a structure for applying an elastic force or an urging force that moves at least one of the paths of the cut portion from the position before the connection. apparatus. 5. An electric element having a conductive portion which is arranged in or between substrates on which a pattern through which an output of a battery serving as a power source directly flows is formed and which has a conductive portion extending to connect the pattern. Alternatively, a metal piece, a low melting point solder that connects the conductive portion of the electric element or metal piece to each pattern of the board, and a biasing member that biases the electric element or metal piece in a direction away from the printed board. A thermal fuse device comprising: 6. A pair of contact pieces made of a conductive material, which are arranged in the middle of a path to which the output of a battery serving as a power source of a circuit or a device is directly applied, and which are positioned so that their tip portions overlap each other. A thermal fuse device comprising: a soldering block having a low melting point, which is placed on one side of the pair of contact pieces while keeping the tips of the pair of contact pieces in contact with each other. 7. A third contact piece is arranged in parallel to the contact piece whose tip portion fluctuates according to the melting of the solder mass, and in contact with the contact piece fluctuating according to the melting of the solder mass. The thermal fuse device according to claim 6, wherein the thermal fuse device is provided.